Bhagavad Gita 4.35
Having known That, you shall never again be confounded; and, O Arjuna, by the power of that wisdom, you shall see all these people as if they were your own Self, and therefore as Me.
यज्ज्ञात्वा न पुनर्मोहमेवं यास्यसि पाण्डव।
येन भूतान्यशेषेण द्रक्ष्यस्यात्मन्यथो मयि॥yajjñātvā na punarmohamevaṃ yāsyasi pāṇḍava|
yena bhūtānyaśeṣeṇa drakṣyasyātmanyatho mayi||
English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).